- High thyroid antiperoxidase
- 1. Hashimoto's thyroiditis
- 2. Graves' disease
- 3. Pregnancy
- 4. Subclinical hypothyroidism
- 5. Family history
Thyroid antiperoxidase (anti-TPO) is an antibody produced by the immune system and that attacks the thyroid gland, resulting in changes in the levels of hormones produced by the thyroid. Anti-TPO values vary from laboratory to laboratory, with increased values usually indicative of autoimmune diseases.
However, the amount of this thyroid autoantibody can increase in several situations, so it is important that the diagnosis is made taking into account the result of other tests related to the thyroid, such as other thyroid autoantibodies and TSH, T3 and T4 levels. Know the tests that are indicated to evaluate the thyroid.
High thyroid antiperoxidase
Increased values of thyroid antiperoxidase (anti-TPO) are usually indicative of autoimmune thyroid diseases, such as Hashimoto's thyroiditis and Graves' disease, for example, however it may be increased in other situations, such as pregnancy and hypothyroidism. The main causes of increased thyroid antiperoxidase are:
1. Hashimoto's thyroiditis
Hashimoto's thyroiditis is an autoimmune disease in which the immune system attacks the thyroid, disrupting the production of thyroid hormones and resulting in symptoms of hypothyroidism, such as excessive tiredness, weight gain, muscle pain and weakening of hair and nails.
Hashimoto's thyroiditis is one of the main causes of an increase in thyroid antiperoxidase, however it is necessary to carry out further tests to complete the diagnosis. Understand what Hashimoto's thyroiditis is, symptoms and how to treat it.
2. Graves' disease
Graves' disease is one of the main situations in which thyroid antiperoxidase is high and happens because this autoantibody acts directly on the thyroid and stimulates the production of hormones, resulting in characteristic symptoms of the disease, such as headache, wide eyes, weight loss, sweat, muscle weakness and swelling in the throat, for example.
It is important that Graves' disease is identified and treated correctly to relieve symptoms, the treatment being indicated by the doctor according to the severity of the disease, and the use of medication, iodine therapy or thyroid surgery may be recommended. Learn more about Graves' disease and how it is treated.
3. Pregnancy
Due to hormonal changes common in pregnancy, it is possible that there are also changes related to the thyroid gland, including the increase in levels of thyroid antiperoxidase in the blood.
Despite this, the pregnant woman does not necessarily have changes in the thyroid. Therefore, it is important to measure anti-TPO at the beginning of pregnancy so that the doctor can monitor levels during pregnancy and check the risk of developing thyroiditis after delivery, for example.
4. Subclinical hypothyroidism
Subclinical hypothyroidism is characterized by a decrease in the activity of the thyroid gland that does not generate symptoms and that is only noticed through blood tests, in which normal T4 levels and increased TSH are verified.
Although the dosage of anti-TPO is not normally indicated for the diagnosis of subclinical hypothyroidism, the doctor may order this test to assess the progression of hypothyroidism and to check whether the person is responding well to treatment. This is possible because this antibody acts directly on the enzyme that regulates the production of thyroid hormones. Thus, when measuring thyroid antiperoxidase in subclinical hypothyroidism, it is possible to verify whether the decrease in the amount of anti-TPO accompanies the regularization of TSH levels in the blood.
Learn how to recognize and treat hypothyroidism.
5. Family history
People who have relatives with autoimmune thyroid disease may have altered values of thyroid antiperoxidase antibody, which is not an indication that they also have disease. Therefore, it is important that the value of the anti-TPO is evaluated along with the other tests requested by the doctor.
